class Solution {
    public int climbStairs(int n) {
        if(n == 1) {
            return 1;
        }
        if(n == 2) {
            return 2;
        }
        int[] dp = new int[n + 1];
        dp[1] = 1;
        dp[2] = 2;
        for(int i = 3;i < n + 1; i++) {
            dp[i] = dp[i - 1] + dp[i - 2];
        }
        return dp[n];
    }
    public int rob(int[] nums) {
        int[] dp = new int[nums.length + 2];
        for(int i = 2; i < dp.length; i++) {
            dp[i] = dp[i - 2] + nums[i-2];
        }
        return Math.max(dp[nums.length],dp[nums.length + 1]);
    }
}
